Add support for SQL Views (#1044)

Co-authored-by: Kyle Conroy <kyle@conroy.org>

Author: Robert Holt

internal/compiler/compile.go

@@ -14,7 +14,6 @@ import (
 	"github.com/kyleconroy/sqlc/internal/multierr"
 	"github.com/kyleconroy/sqlc/internal/opts"
 	"github.com/kyleconroy/sqlc/internal/sql/ast"
-	"github.com/kyleconroy/sqlc/internal/sql/catalog"
 	"github.com/kyleconroy/sqlc/internal/sql/sqlerr"
 	"github.com/kyleconroy/sqlc/internal/sql/sqlpath"
 )
@@ -54,7 +53,7 @@ func enumValueName(value string) string {
 }
 
 // end copypasta
-func parseCatalog(p Parser, c *catalog.Catalog, schemas []string) error {
+func (c *Compiler) parseCatalog(schemas []string) error {
 	files, err := sqlpath.Glob(schemas)
 	if err != nil {
 		return err
@@ -67,13 +66,13 @@ func parseCatalog(p Parser, c *catalog.Catalog, schemas []string) error {
 			continue
 		}
 		contents := migrations.RemoveRollbackStatements(string(blob))
-		stmts, err := p.Parse(strings.NewReader(contents))
+		stmts, err := c.parser.Parse(strings.NewReader(contents))
 		if err != nil {
 			merr.Add(filename, contents, 0, err)
 			continue
 		}
 		for i := range stmts {
-			if err := c.Update(stmts[i]); err != nil {
+			if err := c.catalog.Update(stmts[i], c); err != nil {
 				merr.Add(filename, contents, stmts[i].Pos(), err)
 				continue
 			}

internal/compiler/engine.go

@@ -42,7 +42,7 @@ func (c *Compiler) Catalog() *catalog.Catalog {
 }
 
 func (c *Compiler) ParseCatalog(schema []string) error {
-	return parseCatalog(c.parser, c.catalog, schema)
+	return c.parseCatalog(schema)
 }
 
 func (c *Compiler) ParseQueries(queries []string, o opts.Parser) error {

internal/compiler/output_columns.go

@@ -3,13 +3,39 @@ package compiler
 import (
 	"errors"
 	"fmt"
+	"github.com/kyleconroy/sqlc/internal/sql/catalog"
 
 	"github.com/kyleconroy/sqlc/internal/sql/ast"
 	"github.com/kyleconroy/sqlc/internal/sql/astutils"
 	"github.com/kyleconroy/sqlc/internal/sql/lang"
 	"github.com/kyleconroy/sqlc/internal/sql/sqlerr"
 )
 
+// OutputColumns determines which columns a statement will output
+func (c *Compiler) OutputColumns(stmt ast.Node) ([]*catalog.Column, error) {
+	qc, err := buildQueryCatalog(c.catalog, stmt)
+	if err != nil {
+		return nil, err
+	}
+	cols, err := outputColumns(qc, stmt)
+	if err != nil {
+		return nil, err
+	}
+
+	catCols := make([]*catalog.Column, 0, len(cols))
+	for _, col := range cols {
+		catCols = append(catCols, &catalog.Column{
+			Name:      col.Name,
+			Type:      ast.TypeName{Name: col.DataType},
+			IsNotNull: col.NotNull,
+			IsArray:   col.IsArray,
+			Comment:   col.Comment,
+			Length:    col.Length,
+		})
+	}
+	return catCols, nil
+}
+
 func hasStarRef(cf *ast.ColumnRef) bool {
 	for _, item := range cf.Fields.Items {
 		if _, ok := item.(*ast.A_Star); ok {

internal/endtoend/testdata/create_view/mysql/go/db.go

@@ -0,0 +1,5 @@
+-- name: GetFirst :many
+SELECT * FROM first_view;
+
+-- name: GetSecond :many
+SELECT * FROM second_view WHERE val2 = $1;

internal/endtoend/testdata/create_view/mysql/go/models.go

@@ -0,0 +1,10 @@
+CREATE TABLE foo (val text not null);
+
+CREATE VIEW first_view AS SELECT * FROM foo;
+CREATE VIEW second_view AS SELECT * FROM foo;
+CREATE VIEW third_view AS SELECT * FROM foo;
+
+ALTER TABLE foo ADD COLUMN val2 integer;
+CREATE OR REPLACE VIEW second_view AS SELECT * FROM foo;
+
+DROP VIEW third_view;

internal/endtoend/testdata/create_view/mysql/go/query.sql.go

@@ -0,0 +1,12 @@
+{
+  "version": "1",
+  "packages": [
+    {
+      "engine": "mysql",
+      "path": "go",
+      "name": "querytest",
+      "schema": "schema.sql",
+      "queries": "query.sql"
+    }
+  ]
+}

internal/endtoend/testdata/create_view/mysql/query.sql

@@ -0,0 +1,5 @@
+-- name: GetFirst :many
+SELECT * FROM first_view;
+
+-- name: GetSecond :many
+SELECT * FROM second_view WHERE val2 = $1;

internal/endtoend/testdata/create_view/mysql/schema.sql

@@ -0,0 +1,10 @@
+CREATE TABLE foo (val text not null);
+
+CREATE VIEW first_view AS SELECT * FROM foo;
+CREATE VIEW second_view AS SELECT * FROM foo;
+CREATE VIEW third_view AS SELECT * FROM foo;
+
+ALTER TABLE foo ADD COLUMN val2 integer;
+CREATE OR REPLACE VIEW second_view AS SELECT * FROM foo;
+
+DROP VIEW third_view;

internal/endtoend/testdata/create_view/mysql/sqlc.json

@@ -0,0 +1,12 @@
+{
+  "version": "1",
+  "packages": [
+    {
+      "engine": "postgresql",
+      "path": "go",
+      "name": "querytest",
+      "schema": "schema.sql",
+      "queries": "query.sql"
+    }
+  ]
+}

internal/endtoend/testdata/create_view/postgresql/go/db.go

@@ -302,10 +302,6 @@ func (c *cc) convertDeleteStmt(n *pcast.DeleteStmt) *ast.DeleteStmt {
 }
 
 func (c *cc) convertDropTableStmt(n *pcast.DropTableStmt) ast.Node {
-	// TODO: Remove once views are supported.
-	if n.IsView {
-		return todo(n)
-	}
 	drop := &ast.DropTableStmt{IfExists: n.IfExists}
 	for _, name := range n.Tables {
 		drop.Tables = append(drop.Tables, parseTableName(name))
@@ -667,7 +663,14 @@ func (c *cc) convertCreateUserStmt(n *pcast.CreateUserStmt) ast.Node {
 }
 
 func (c *cc) convertCreateViewStmt(n *pcast.CreateViewStmt) ast.Node {
-	return todo(n)
+	return &ast.ViewStmt{
+		View:            c.convertTableName(n.ViewName),
+		Aliases:         &ast.List{},
+		Query:           c.convert(n.Select),
+		Replace:         n.OrReplace,
+		Options:         &ast.List{},
+		WithCheckOption: ast.ViewCheckOption(n.CheckOption),
+	}
 }
 
 func (c *cc) convertDeallocateStmt(n *pcast.DeallocateStmt) ast.Node {